This invention relates to a head stabilizer accessory for use with head immobilizing devices such as head immobilizing devices used with panoramic x-ray machines.
There are numerous instances in the health care field wherein it is necessary to "stabilize" the patient's head during treatment. Consequently, a variety of devices for immobilizing the human head have been developed and illustrative of such devices are those used with panoramic x-ray machines. Panoramic x-ray equipment operates to arcuately scan a dental patient's oral structures with a narrow x-ray beam directed through the mouth region of the head toward a film carrier on the opposite side of the patient's head. Although the x-ray equipment traverses an arcuate path around the patient's head, the beam is discontinuous during traverse so as not to irradiate the spine. Also the beam direction shifts relative to the film carrier during a traverse so that a full mouth oral structure image is obtained on a rectangular film supported in the carrier. It is important that the patient's head not move during the scan period for any movement during such period distorts at least part of the x-ray image.
The head immobilizing device described, for example, in U.S. Pat. Nos. 3,521,057 and 3,936,641 exemplify commercially successful units of this type. These immobilizing devices are characterized by two horizontally adjustable vertical or upright elements for positioning the head therebetween. Ordinarily there is also a chin rest which may or may not be adjustable. While this type of head immobilizer of the prior art restricts head movement downward and side-to side it does not prevent upward or backward movement of the head. The latter shortcoming of the device presents no problem with the "normal" patient who has the ability to hold his head absolutely still for 10 to 15 continuous seconds but this inability to prevent upward or backward movement of the head has been found to be a frequent cause of malpositioning when the patient is a child or handicapped person.